Top seeds survive another day at Australian Open

The Australian Open top seeds have survived another day as the hot conditions turned cold, though Aussie firebrand Nick Kyrgios has gone home.

Andy Murray's quest for a maiden Australian Open title remains on track after a straight sets victory over Russian qualifier Andrey Rublev, though questions over the second week remain.

Reigning champion Novak Djokovic on Tuesday said his tough opening bout against Fernando Verdasco was the best preparation for his title defence, having to approach the opening round and the tournament "with the right intensity right from the blocks."

Rublev however proved a sedate opponent, falling in straight sets: 6-3, 6-0, 6-2, barely challenging the reigning world champion on serve. A twisted ankle in the third set is also adding concerns to the world no. one's third round match against Sam Querrey.

"I don't know how bad it is, just normally if it's something like severe, a serious ankle injury, you can't put weight on your foot," Murray told reporters. The Brit "heard a few sort of little crackles, and it was sore" during the match, but "I was moving fine on it."

"There's not a whole lot you can do apart from (icing) just now. (I'll) see in the morning how it feels when I wake up. But hopefully it will be all right."

Querrey will be a true test in the lead up to the finals, but Murray insisted he' ll be ready after some tough matches in the Doha warm up tournament and his challenging first round.

"I had some tough moments in that one," Murray said.

"I was down a break in the first two sets. It was a pretty long one in tough conditions."

"I think I played as well as I can play today, I was really pleased with how I played especially towards the end of the match," Evans said, admitting he's searching for a clothing sponsor after coming off contract with Nike in December following reporters questioning his non-colour coordinated attire.

"No (offers coming in), not at the minute anyway. We'll see. Another win, I might get one."

Women's top seed Angelique Kerber has also progressed, though with a little more court time under her belt, defeating German compatriot Carina Witthoeft with a scrappy 6-2, 6-7(3), 6-2 in a little over two hours.

"I was doing a lot of mistakes in the important moments," Kerber told reporters.

"But at the end, I'm happy that I won the match.

"It was not so easy, the conditions were also a little bit difficult today."

The third night was also difficult for Aussie Nick Kyrgios whose inner demons resurfaced, reigniting debate over the team supporting Australia's best hope for a home grand slam win.

It was a "banged up body" and a lack of preparation and the "poor management" of his "team" during the offseason that led to the 6-1, 7-6 (1), 6-4, 6-2, 8-10 loss, Kyrgios told reporters post match, though it's the mental side of the game that's letting him down.

"Mental side of things are big for me, that's where a coach would be good," Kyrgios said after noting he's the only player in the top 100 without one.

"But, I mean, he played well, as well. (I) Thought he served great today.

"I've got a lot of respect for him. He fights hard. He deserved it."

Duan Yingying is China's only remaining singles player in the main draw, though she'll have to be at her very best when she takes on Venus Williams in the third round on Friday.